Application of finely divided material to articles of manufacture



Jan. 28, 1936" M. M. MERRITT 2,028,796

APPLICAT ION OF FINELY DIVIDED MATERIAL TO ARTICLES OF MANUFACTURE FiledMay 14, 1952 3 Sheets-Sheet 1 Jan, 28, 1936.

M. M. MERRITT APPLICATION OF FINELY DIVIDED MATERIAL T0 ARTICLES OFMANUFACTURE 5 Sheets-Sheet 2 Filed May 14, 1952 Jam-28, 1936. M, R,2,028,796

APPLICATION OF FINELY DIVIDED MATERIAL TO ARTICLES OF MANUFACTURE lmented Jan. 28, 1936 airs!) STATES PATENT OFFICE APPLICATION OF FINELYDIVIDED MATE- to The Tanning Process Company, Boston,

Mass., a corporation of Massachusetts Application May 14, 1932, SerialNo. 611,425

27 Claims.

This invention relates to the treatment of articles of manufacture withfinely divided material. While the invention is described with referenceto the coloring of pieces of leather with nebulized dye material, it isto be understood that the invention and various importantcharacteristics and features thereof may have other applications anduses.

In the coloring of pieces of leather with the aid of hand-supportedspraying devices, as heretofore practiced, a piece of leather was placedupon a slanting work supporting surface in a sort of booth with anoverhead hood to draw off the vapors and excess nebulized material. Theoperator standing at the entrance to the booth directed the nebulizedmaterial upon the work and moved it back and forth at different levelsin an attempt to cover the surface of the leather in a uniform mannerand with the requisite amount of dye material to secure the desiredshade of color.

, An expert in the work who exercised extreme care secured verygood'results for a limited time. It will be readily understood, however,that the quality of the work depended entirely upon the skill, theendurance, and the faithfulness of the operator to his conception of afinished piece of work of the quality desired by the manufacturer. Withsome operators the factor of endurance may have been the most important,it being obvious that, after several hours, fatigue, particularly in themuscles of the arm and hand, would militate against the attainment ofgood results. More often, however, failure to get good results was dueto the speed of the traveling spray being too great for any but the mostskillful operators to control properly the application thereof to thework and to the fact that only a small part of a piece of leather wastreated at any given instant. There was thus required a high degree ofaccuracy in eyesight and in control of the application of the spray inorder to secure uniform results in all parts of the work piece. As amatter of fact pieces of leather colored, or otherwise treated, with theaid of nebulizers or spray devices in accordance with methods heretoforecommonly practiced were rarely uniform in quality or in color. The goodsthus manufactured were, however, saleable at a price and this mayaccount in part, but only in part, for the fact that in the course ofmany years so little has been accomplished in the many attempts made toovercome the deficiencies and defects of methods and mechanisms longemployed in the coloring of leather.

It is an object of the invention to secure uniformity in the quality ofthe product obtained in the treatment of articles of manufacture byliquid material in finely divided form. It is a further object of theinvention to standardize the treatment of such articles and to speed upproduction while maintaining high quality in the appearance 5 of thefinished product.

To these ends and in accordance with important characteristics of theinvention, a controllable body of air, adequate in volume, is firsttreated with nebulized or finely divided liquid material andsubsequently moved in a direct line to an exposed surface of an articleplaced substantially centrally in said body of air for treatment. Thepurpose is to secure wide and uniform distribution of the finely dividedliquid material before 5 it reaches the piece of work to be treated andthen to deposit the dispersed material uniformly on the exposed surfaceof said work piece.

In the method as practiced, nebulized or finely divided liquid materialin a relatively restricted amount of air is projected in a givendirection and at high speed into a controllable body of air ofsubstantially greater volume and moving in a different direction to thepiece of work to be treated. It follows that air currents are set up 5in the body of air by the entering nebulized material which assist inthe desired distribution of the material throughout the controllablebody of air. Moreover, by projecting the nebulized material, during itsintroduction into the controllable body of air, in a direction otherthan directly toward the work, more time is given to effect the desireddistribution of such material than if it were shot directly toward thework.

Preferably and as disclosed herein, the controllable body of air isdrawn to and through a space all around the periphery of the piece ofwork, the purpose being to cause the treated air to move over thesurface of the piece of work from central portions thereof out to all ofits marginal portions, so that uniform distribution of the finelydivided material over the whole surface of the work may be secured.

For practising the method by which articles of manufacture may betreated with finely divided or nebulized liquid material there isprovided, in the illustrated construction, a chamber as the mostconvenient means of securing a controllable body of air of the desiredvolume movable directly toward a piece of work to be treated, togetherwith means operative to introduce a cloud of finely divided materialinto the controllable body of air and mix it thoroughly therewith. Inorder to facilitate distribution of the finely divided materialuniformly through the air moving toward the work, said means is arrangedto project the said material into said controllable body of air at anangle to its direction of movement. This angle may be varied within widelimits but should not be such as to project any part of the finelydivided liquid mawrial directly toward the piece of work.

Preferably and as shown, the chamber has an inlet for air and also anoutlet, a work supporting means being located at or adjacent to theoutlet and centrally of the latter so that the treated body of air iscontrollable to a larger degree than would otherwise he the case byreason of the fact that the air must escape all around the periphery ofthe piece of work. Due to this arrangement for the escape of thematerial-laden air, it passes over, and treats all portions of thesurface of the piece of work from the center outwards te the peripheralportions thereof. To

facilitate uniform distribution of the material over the article beingtreated provision is made .to move the piece of work, for example, bymoving the work support at a predetermined speed whereby the effect ofvariations in the direction and speed of currents of air set up withinthe body of air moving toward the piece of work will be largelyneutralized.

In the illustrated construction, the controllable erated piston isconnected to the shutter to move the latter in timed relation to theaction of the nebulizer, the construction and arrangement being suchthat when, after a. short interval, the nebulizer has started tonebulize material at the normal or predetermined pressure the pistonmoves to retract the shutter to inoperative position. The shutter may bemoved in the opposite direction, that is, to operative position, bymeans of a spring, the air being released from the piston cylinder itopermit retraction of the piston) by a release valve controlled by thesame switch which starts the pneumatic means and, perforce, thenebulizer in operation. a 4

These and other important characteristics and 5 body of air within thechamber is caused to move toward the work support by having a bloweroperative to withdraw air from. the chamber through aspace surroundingthe periphery of the work support upon which the work rests. To.

assist in drawing air into the chamber a fan is provided near the inletthereof but the capacity of the fan .is substantially less than thecapacity of said blower so that the latter may draw upon the air at theoutlet in the manner already described.

It is a well-known fact that upon starting a nebulizer (of the sizecommonly used in manufacturing operations) there is almost invariablyejected a small body of liquid material and also droplets ofconsiderable size which, if allowed to reach the work, would produceimperfections in the appearance thereof. Hence, it is desirable toprevent the introduction of such material from the nebulizer into thechamber. Furthermore, in

order to secure work of high quality notable for the uniformity ofitsfinished surface it is desirable that the nebulized material beintroduced into thechamber invariably at the pressure selected as thenormal pressure at which a given material should be nebulized to producea uniferm, finely divided material. For both of these reasons there isprovided, in the illustrated construction, means to controltheintroduction of nebulized material into the chamber in such manner as tosecure, in the chamber, onlg. finely divided material uniform in itsfineness and distributlon. This is conveniently accomplished through theprovision or a shutter operable in timed relation to the operation ofthe nebulizer to intercept unnebulized material or only partiallynebulized material, the said shutter being withdrawn at the proper timeto permit of introduction of material nebulized at thenormal pressure.Preferably also the shutter is operated in timed relation to thenebulizer to prevent entrance of nebulized or only partially nebulizedpneumatic means which furnishes air under pressure to the nebulizer. Asillustrated, an air-optn detail and then pointed out more particularlythe appended claims.

In the drawings,

Fig. l is a view in side elevation and partly in section of a machineillustrating one embodiment of the invention;

Fig. 2 is a sectional view of the machine shown in Fig. 1 taken alongthe line II-=-1I and looking in the direction of the arrows;

Fig. 3 is a detail view partly in section of the liquid supplying andnebulizing devices;

Fig. 4 is a vertical section through the nebulizing device;

Fig. 5 is a. section along the line VV in Fig. 4;

Fig. 6 is a detail view of a special means for controlling ashutter intimed relation to the nebulizer;

Fig. 7 is a view of the device shown in Fig. 6 looking from the left inthe latter figure along the line VIIV11; and

Fig. 8 is a view taken along the line VIII-VIII of Fig.

in the illustrated machine, which is specially designed for' theapplication of coloring material to pieces of leather, there is providedachamber l0 having at its upper end an inlet l2 for the entrance of airand at its lower end an outlet at it for the exit of air. At the outletof the chamber there is provided a work support i6 upon the uppersurface of which a piece of leather [8 may be supported in the path ofthe air passing through the chamber. For drawing air into the chamberthrough the inlet l2 and causing it to move toward the work support l6there is provided a suitable fan 20 located in the upper end of thechamber below the inlet l 5. Preferably and as shown, means is providedfor drawing air from the chamber !0 at the outlet thereof, the saidmeans comprising a blower 22 of a well-known construction arranged to bedriven by belt connections with a motor 24, the capacity of the blower22 being substantially greater than that of the fan 20 so that there isa. distinct tendency to draw the air downwardly through chamber ID tothe piece of work supported on the work support l6. As shown, the outletI4 is constructed so as to provide an opening all around the peripheryof the lower end of the chamber ID, the work support it being largerthan the lower end of the chamber so that the air is directed in alateral direction at the outlet from the chamber, the idea being tocause, air currents to spread outwardly in all directions from a centralportion of the table. At a point intermediate between the inlet and theoutlet M of the chamber there is provided an opening 26 through whichnebulized material may be introduced into the chamber ID from a spraygun or nebulizer 28. It will be noted that the cloud of nebulized orotherwise finely divided material is projected at an angle to the pathof movement of the body of air passing through the chamber I from theinlet I2 to the outlet I 4 thereof. In this way the nebulized materialis well distributed within the larger body of air passing through thechamber before any part of the nebulized material reaches the piece ofwork I8 on the work support I6. Due to the suction of the blower 22 uponthe air at the restricted peripherally arranged outlet of the chamberI0, the air spreads out in all directions from a central portion of thework support to the periphery thereof. Hence the nebulized material isfurther distributed to include all portions of the piece of work exposedfor treatment.

As illustrated the work support I6 is carried at .the upper end of avertical shaft 30 (Fig.' 1) to which is secured a collar 32 arranged torest upon the upper side of a cross piece 34 by which the collar andshaft are supported. Secured to or integral with the collar 32 is aspiral gear 36 (Figs. 1 and 2) arranged to be in mesh with a worm 38secured to the horizontal shaft 40 carried by bearings in brackets 42and 44. At its other end the shaft 40 carries a pulley 46 around whichpasses a belt 48 to a second pulley 50 secured to armature shaft 52 ofmotor 54, the arrangement being such that the table I6 is rotated at arelatively slow rate while the motor 54 is running. It is clear that byrotation of the table I6 a piece of work such as thatshown at I8 ismoved at a uniform speed in a plane transverse to the direction of thepath of movement of the air through the chamber I0, therebysubstantially neutralizing the effect of variations in the distributionof the nebulized material in the body of air moving toward the work andalso of variations in air currents set up by both the fan 20 and theblower 22 in forcing air through the container and out around theperiphery of the table I6 at the outlet of the chamber.

Conveniently the motor 54 is utilized to provide air under pressure foreffecting nebulizing of a liquid dye material at the nozzle of thenebulizer 28. For this purpose the motor shaft 52 (Fig. 2

is provided with a pulley 60 about which passes a belt 62 to a secondpulley 64 on a shaft 66 of an air compressor indicated by referencecharacter 68. From the air compressor 68 a tube (Figs. 2 and 3) carriesthe air to an air controlling device 72 which is conveniently a widelyused commercial unit known as an aerograph control comprising an airstrainer or cleaner, a pressure reducing valve and a pressure indicatorI4. While the air compressor 68 sends air into the pipe 10 at a pressurearound one hundred pounds, the reducing valve brings the pressure downto a desired lower pressure. In this case the tube I8 carries air underan adjusted pressure of six pounds to the nebulizer 28 (Figs. 1, 3 and4). As will be evident from an inspection of Fig. 4 the air from tube 18is conducted by passageways 80, ,82 to a chamber 84 from which it isallowed to escape through a circular opening into a chamber 86surrounding a liquid carrying nozzle 88, the air passing from chamber 86through a circular opening 90 (Fig. 5) surrounding the reduced circularend of the nozzle 88. By the force of the air rushing from therestricted space 90 the liquid is drawn from the nozzle 88 and reducedto a finely divided or nebulized condition. Furthermore, the pressure ofthe air escaping from the opening 90 is such as to project the nebulizedmaterial with considerable force into the chamber where the cloud ofnebulized material becomes well distrib- 3 uted in the body of airtraveling toward the piece of work to be treated.

The nebulizer comprises a receptacle 92 (Fig. 3) for a liquid materialto be projected into the chamber [0, a pipe 94 (Figs. 3 and 4) beingarranged to dip well below the surface of the liquid constantlymaintained in the receptacle 92 to conduct the liquid via passageway 95to the nozzle 88 of the nebulizer 23 as it is drawn thereto by theaction of the air escaping under pressure through the opening 90. Formaintaining the liquid at a certain level in the receptacle 92 there isprovided a cup 96 (Fig. 3) supported at the proper level by a bracket 98attached to the wall of the chamber I0, the cup 66 being constructed andarranged to receive the neck portion of a standard size bottle containerI00 (Fig. 3 of liquid dye material. This is the well-knownt-barometricfeed arrangement for maintaining within the cup 96 a liquid in an amountand at a level determined by atmospheric pressure. From an opening inthe bottom of the cup 96 there extends a tube I02 which communicates bya second tube I04 with the bottom of the receptacle 92. It will bereadily understood that the level of the liquid in the receptacle 92will be maintained through the connecting tubes I02, I04 atsubstantially the same level as the liquid in the cup 96. The lower endof the tube I02 is normally closed through proper manipulation of avalve closure contained in a valve I06, it being possible to manipulatethe valve closure so as to discharge all the liquid from the receptacle92 and from the cup 96 when it is desired to change from one liquid toanother, for instance, in substituting one dye or color for another.

When it is desired to introduce nebulized material from the nebulizer 28into the chamber I0, the operator throws a switch indicated at IIO(Fig. 1) whereupon the motor 54 is energized to operate the aircompressor 68 whereupon air pressure is quickly built up in the air lineI0 and in part of the device I2 by reason of the resistance ofiered bythe reducing valve in the device I2, and material is sprayed from thenozzle 88 beginning at a low pressure but quickly reaching the maximumof six pounds fixed by the adjustable reducing valve. At the beginningof the spraying or nebulizing operation, the liquid material is apt tobe ejected in relatively large droplets which, if allowed to reach thechamber I0, would be almost certain to be deposited upon the work andcause an imperfection on the surface of the latter. Hence, a shutter orshield member, hereinafter more specifically described, is mounted inthe wall of the chamber I0 in such manner that it may be readily shiftedinto a position where it is interposed between the end of the nozzle 88and the opening 26 in the chamber wall, the shutter or shield being leftin position until the air pressure has risen to a point where it isoperating at its normal maximum pressure. This requires only a second ortwo after which the shutter is withdrawn to permit the nebulizedmaterial to be introduced directly into the chamber I0. In order tofacilitate introduction of a uniform amount of nebulized material duringthe treatment of successive pieces of work, the switch H0 willpreferably be of a time controlled type such as that afforded by thewell-known mark-time switch, disclosed in United States Letters PatentNo. 1,773,697, granted Aug. 19, 1930, upon application of M. H. Rhodes.As stated above, the motor 54 operates not only the compressor 68 butalso the rotating means for the table I 6. Hence, when the switch H isoperated to initiate a work treating operation, the table I6 is set inrotation and at the" same time the nebulizing device becomes operativeto introduce nebulized material into the chamber I0. Clearly, when theswitch, at the end of a timed period (such as fifteen seconds)automatically shuts off the current to the motor 64, the table comes torest and the nebulizer becomes inoperative through lack of airpresliquid condition of the sprayed material, an opensure.

For introducing air to the top of the chamber I0 throughthe inlet I2there is provided a conduit I24 (Fig'. 1) which may lead to the outsideair through an opening I26. However, in order to provide for airconditioned both as to temperature and humidity in such degree as tomaintain the ing I28 is provided in the upper wall of the conduit .I24leading to an air conditioner (not shown) of any well-known constructionwhere the air may be prepared at the proper temperature and humidity forintroduction into the chamber I0. It has been found that, if the airdrawn into the chamber I0 be too dry, it would be detrimental if notdestructive with respect to the desired results through its dryingefl'ects on the spray. To control the amount of air drawn through theopenings I26 and I28, there is provided a valve member I30 which may bemanipulated by means of -a cord or cable I32, the end of which isbrought down within reach of the operator, a second valve member I34being also provided to serve as a further control of the air passingthrough the conduit I24 to the inlet I2 of the ranged to be driven fromany suitable source of power. As before stated, the air is pulled fromthe lower end or outlet of the chamber I0 by means ofthe blower 22mounted at the end of an outlet pipe I50 which projects well under thetable 68, the blower 22 discharging-the air withdrawn from the chamberI0 througha pipe I52 to the outdoor air or to a suitable receptacle forreclaiming solvents or dye materials which escape from the chamber I0.

It will be noted that the chamber I0 has an inside wall I60 which ispreferably made of sheet absorbent material such as a commercialwall-board product known as homosote" which, because of the facilitywith which it absorbs liquid material, retains nebulized material comingin contact therewith and thus prevents any spattering or dripping ofmaterial from the side walls of the chamber to the work or to the worksupport.

Preferably, and as shown, a baflle plate, I62 having a median openingI64 is provided between the fan 20 and the level of the nebulizer 28. By

reason of the presence of the baflle plate I62 nebulized air isprevented from reaching the upper end of the chamber l0 where it wouldbe likely to collect upon the fan 20. Moreover, because of therelatively restricted size of the opening I64 inthe baflle plate I62,air currents are set up in the air passing through the opening I64 tothe lower part of the chamber I0 which contribute to the desireddistribution of the nebulized material from the nebulizer 28 in thelarger In the illustrated device (Figs. 6, 1 and 8) for v moving ashutter in timed'relation tfi the operation of the nebulizer 28 there isprovided a lever I10 fulcrumed at I12 on a wall of the cham-q ber I0,the lever I'I0'having a pin-and-slot connection (Fig. 6) with a shutterI14. As most clearly shown in Fig. 7, the shutter I14 is guided bymembers I16 for'sliding movement in a direction transversely of theopening 26 in the adjacent wall of the chamber I0, the shutter I 14having an opening I18 (Figs. 6 and 8) which may be'made to coincide withthe opening 26, thus permitting the nebulizer to project the nebulizedmaterial into the chamber I0. As most clearly disclosed in Fig. 8, theshutter I14 is also provided, in an angularly projecting portionthereof, with an elongated slot I which may be positioned over the upperend of apipe I82 leading to a chamber below the work support I6 fromwhich air is drawn by the blower 22 through the exhaust pipe I50. Whenthe opening I18 in the shutter I14 is in alinementwith the opening 26,the slot I80 in shutter I14 is positioned at one side of the upper endof the pipe I82. On the contrary, when the shutter I14 is positioned sothat the opening I18 therein is out of alinement with the opening 26 inthe wall in the chamber, the slot I80 or some part of it, is in aposition over the upper end of the pipe I82 so that material ejectedfrom the nebulizer 28 and unable to enter the chamber due to the closingof the opening 26, may escape through the slot I80 into ,the pipe I82through which it is drawn due to the action of the blower 22.Preferably, and as shown, the outside or exposed surface of the shutterI14 is covered by a sheet I83 of absorbent paper which may be readilyreplaced by a similar piece of paper since it is held in place by clipssuch as those shown at I84, It being understood that the sheet ofabsorbent paper is provided with openings corresponding with those atI18 and I80 in the shutter I14.

For'operating the lever I10, there is provided a piston I arranged to bedriven in one direction by air pressure within the cylinder I92,'thepiston I80 having a rod I93 fixedly secured thereto and extendingthrough a cap I94 on the cylinder I92. At its free end the rod I83 isprovided with a link I96 pivotally attached thereto, the other end ofthe link I06 being pivoted at I88'in a forked portion of the lever I10.It will be clear from an inspection of Fig. 6 that the lever I10 isswung in one direction through operation of the piston I90 and that saidlever I10 is arranged to be swung in the other direction by a spring200. Said spring 200 is attached to the upper end of the lever I10 andto a screw-threaded member 202 adjustably mounted within a rotatableinteriorly screw-threaded member 204 held stationary in place against awall of the chamber I0 by means of an eye bolt 206 having an eye portion208 thereof encircling the screw- I threaded member 202 so that thelatter may free- 1y move' longitudinally through the ring 208. Thismovement of the screw-threaded member 202 through the stationary ring208 takes place only when the member 204 is rotated to adjust the member202 axially of the member 208. Ad-

2,028,796 justment of member 202 relatively to the memher 208 is for thepurpose of adjusting the tension of the spring 200.

Preferably, and as shown, air is admitted to the cylinder I92 from theair compressor 68 through a number of interconnected pipes 2I0, in oneof which is a valve member 2I2 containing a rotatable choke va' ve 2I4having a passageway 2H3 therethrough, the choke valve 2I4 beingadjustable to vary the position of the passageway 2I6 in such manner asto change the amount of air which may pass through the pipe 2I0 to theentrance pipe 2I8 leading to the chamber of cylinder I92. It is obviousthat, when the passageway 2I6 in the choke valve 2| 4 is at asubstantial angle to the passageway through the pipe 2I0, air may beadmitted in such restricted amounts as to cause only a slow movement ofthe piston I90 in the chamber I92, to the left in Fig. 6, while, at thesame time, pressure is built up so rapidly in the nebulizer that thelatter is operating to eject nebulized material while the shutter I14 isstill in blocking or closing position with respect to the opening 26 inthe wall of the chamber I0. Finally, however, the piston I90 exerts itsaction upon the lever I10 to shift the shutter I14, thus permitting thenebulizer 28 to introduce the nebulized material directly into thechamber I0. When, at the end of a nebulizing operation, the timecontrolled switch at IIO shuts off the current to the motor 54, thepressure in the nebulizer 28 is promptly reduced through the failure ofthe air compressor 68 so that the nebulizing of the liquid materialtakes place for a time at a pressure substantially below the pressurenormal for such liquid material, in which case the nebulized materialmay contain larger droplets than normal and thus fail to present auniform appearance on the surface of the work. Hence, it is desirable toprevent introduction of this nebulized material at low pressure into thechamber I0. For this reason the shutter I14 should be promptly moved toclose the opening 26 in the chamber. This movement of the shutter I14 isaccomplished by the spring 200 which acts promptly because of thetension under which it was placed when the upper end of the lever I10was swung to the left in Fig. 6 through the action of the plunger I90.In order that the piston I90 in the cylinder I92'may ofier very littleor no resistance to the action of the spring 200 at the instant that thepump 68 stops working, the cylinder I92 is connected to a release valve220 which opens at this time to permit free escape of the air fromcylinder I92 into the air of the room as the piston I90 is moved to theright in Fig. 6 by the spring 200. Due to the ease with which the leverI10 and the piston I90 may be moved by the spring 200, the shutter I14is moved promptly to operative position thus preventing nebulizedmaterial at lower than normal pressure being projected into the chamberI after the switch II 0 cuts 01? current to the motor 54. Preferably andas shown, the release valve 220 is of the solenoid-operated typearranged to be controlled by the switch I I0 so that when'the switch isturned oif at the end of a nebulizing operation, the valve at 220 isopened to permit free escape of air from the cylinder I 92. The valve220 remains open until the switch H0 is turned on to start the motor 54.Then the valve is closed by the solenoid so that pressure may be builtup in the cylinder I92 to operate the piston I00.

To summarize briefly, the operation or the shutter operating means, itis pointed out that the shutter H4 is moved to its operative position intimed relation to the operation of the nebulizer to close the opening 26in the wall of the chamber I0 through which the nebulizer 28 wouldotherwise project partially nebulized material into the chamber I0. Thismovement of the shutter I 14 is accomplished through the opera: tion ofthe spring 200 when the air in the cylinder I92 is allowed to escapethrough the opening of the solenoid-operated valve 220, the opening ofthe valve taking place instantly upon movement of the automatic switchIIO to off position. On the other hand, when the switch H0 is moved toon position and the air compressor 68 is thus started to furnish airunder pressure for operating the nebulizer 28, the shutter I14 is moved,after a predetermined interval, to inoperative or uncovering positionwith respect to the opening 26, this movement of the shutter beingaccomplished by the plunger I 90 under pressure of air admitted throughthe choke valve 2I4. In order that the shutter I14 may remain in itsoperative or closed position with respect to the opening 26 for a briefbut suificient interval after the starting of the nebulizer 28, thechoke valve 2I4 is so adjusted as to permit only a restricted amount ofair to pass along the pipe 2I0 to the cylinder I92, thereby causing adelayed movement of the piston I90 against the tension of the spring200. Both the spring 200 and the choke valve 2I2 may be readily adjustedto secure the desired timing of the movement of the shutter I14 operatedby piston I 90. It is a well-known fact that, upon starting a nebulizerin operation after it has been at rest, there is almost invariablyejected from the nozzle of the nebulizer a small body of liquid materialwhich would produce an imperfection in the work if it reached thelatter. Furthermore, at the beginning of the application of air underpressure to the nebulizer, the pressure rises to its desired maximumonly after an interval of time so that, during such interval, the airpressure is not up to the point where the nebulized material will be ofthe desired uniform fineness. For both of these reasons it is desirableto have the shutter I14 in position to close the opening 26 until thenebulizer reaches operation at the desired or normal pressure for thetype of liquid preparation which is being nebulized. It is for thisreason that the shutter I14 remains in place for a substantial intervalafter the beginning of the nebulizing of the liquid preparation by thenebulizer 28. After the desired interval, however, the shutter isremoved to inoperative position through the action of the piston I90 sothat the nebulized material is projected into the chamber I0.

In the operation of the machine a piece of work, such as a skin I8, isplaced upon the work support I6 in such manner that the intersection ofthe transverse and longitudinal axes of the piece of work coincides, atleast roughly, with the axis of the shaft 30. The door I66 is thenclosed and the switch IIO manipulated to start the motor 54. Through theoperation of the motor 54 the table or work support I6 isrotated and aircompressor 68 and nebulizer 28 set in operation. Due to the presence ofthe shutter I14 in operative position, the first part of the material tobe nebulized does not reach the chamber I0. In a second or two, however,the shutter I14 is moved to inoperative position whereupon the nebulize"material is then introduced directly into the chamber I0, thoroughlymixed with the air passof the suction through the outlet I which car--tends entirely around the periphery of the table It, the nebulizedmaterial is uniformly distributed, such. distributidn being facilitatedalscg by rotation of the table It. In a period of time which may be asshort as fifteen seconds, the

piece E work is uniformly colored or-otherwise treated and is ready forremoval. i

Having descrileed my invention, what I claim as new and desire to secureby Letters Patent of the United States is; 1

1. That improvement in methods of applying a preparation to pieces ofwork, such as sheet material, which comprises forming a cloud-of finelydivided liquid material with a relatively restricted amount of'air,mixing the cloud of finely divided material with a considerably largervolume of air in an enclosed space, and glrawingjon said volume of airat the discharge end of said space to cause it to move in a direct lineto and equally in directions radially over a piece of work placed ortreatment in said space centrally of the discharge end of said spacethereby to secure uniformityiin the deposition of finely divided Iliquid material ;on said giiece of work. I

2. That improvement in methods of applying finely divided material topieces of work, such as sheet material, which comprises providing in anenclosed space a body of air moving continuouslyin a downward directiontoward a piece of work placed gentrally in said space to be treated,forming a cloud of finely divided liquid material, intro ducing intosaid body of air at an angle to its downward dirwtion of movement saidcloud of finely divided material, and drawing on said body of air at thedischarge end of said enclosed space to cause it to move in a directline to and equally in all directions radially over the piece of work tobe treated thereby to secure uniformity in the finely divided materialto pieces of work, such as sheet material, which comprises blowing abody of air through an enclosed space and simultaneously therewithdrawing on said body of air at the discharge end of said enclosed spacewith a force substantially greater than that which is applied to blowthe into said space, placing a piece of work to be treated in the bodyof moving air, and intreducing into said body of air at an angle to its;direction of movement a cloud of finely divided material, the drawing ofthe air and its clouds of finely divided material toward the dischargeend of said space causing said finely dirgided material to move in adirect line to and e ually in all directions radially over thepiece ofwrk, thereby to secure uniformity in the deposition of liquid materialon said piece of works 4. in an apparatus for treating such as sheetmaterial, a chamber having an iniet at one end thereof and an outlet atanother end therei if, a substantially circular work supp-art located atthe outlet end of the chamber transversely of said outlet, means locatedbeyond the work support to withdraw air from the chamber uniformly allaround the periphery of said work support. said air-withdrawing meanscausing air I aoaepoo pieces of work,

to move in a direct line to said work support, and means arranged tointroduce finely divided material into air traveling through saidchamber, whereby the said finely divided material may ,be moved in astraight line to and deposited uniformly on a piece of work on saidcircular, we: support. f r;

5. in an apparatus for treating pieces ofwork. such as sheet material, achamber, an inlet at one end of the chamber, an outlet at the other endof the chamber, a substantially circular support for a piece of workpositioned at the outlet of the chamber transversely of said outlet,means to causea body of air to move in a direct line to said support anduniformly over allgieripheral portions of the support to said outlet,and means to produce a cloud of finely divided material and project itinto the moving body of air at an angle to the direction of movementthereof, whereby the finely divided material is; distributed in thethereof to provide space all around the periphery of the work supporti'or the escape of air, and a nebulizer; arranged to introduce nebulizedmaterial into the movingebody of air at an angle to the direction ofmovement thereof whereby the nebulized material is distributed in thebody of air, the walleof the chamberfrom the nebuiizer to the worksupportgbeing straight so that the nebulized air is carried directly tothe piece of work at the outletof said chamber, and said blower beingarranged to withdraw air from the chamber all around the periphery efthe work support, whereby nebulized material is distributed in a uniformmanner over;all portions of the piece of work including peripheralportions of the work piece on said work support. 7

7. In an apparatus for treating articles of manuiacture, a. chamberhaving an inlet at one end thereof and an outlet at another end thereof,a work support located-at the outlet end of the chamber centrally ofsaid outlet, a blower beyond the work support to withdraw air from thechamber, a nebulizer arranged to introduce nebulized liquid materialintcea the air traveling through said chamber, and a baflle plate havinganop'ening through the-middle portion thereof for the passage of ;air,said baffle plate being located above said nebulizer. 7

8-. In an apparatus for treating articles, of manufa cture, a chamberhaving an inlet at one end thereof and an outlet at'another end thereof,a

i 30 tioned at the outlet of the chamber transversely fan; at the inletadapted to draw air into the chamber and blow it therethrough, a woriesupport located at the outlet end of the chamber; centrally of saidoutlet, a blower beyend the :work

support to Withdraw air from the chamber, a nebulizer arranged tointroduce nebulized liquid material into the air travelingthrough saidchamber, and a baiile plate having an opening through the middle portionthereof for the passage of air from the fan, said balile plate beinglocated above said nebulizer and below the fan. Y

9. In an' apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article to betreated located in the'path of movement of the air in said chamber, anebulizer arranged to introduce nebulized liquid material into the airin said chamber, an air compressor connected to said nebulizer, means tooperate the air compressor, means to rotate said support, an electricmotor having an armature shaft carrying pulleys to drive the twolast-mentioned means, and means comprising a time controlled switch incircuit with the motor and arranged to determine the length of operationof the nebulizer'and of the support rotating means.

10. In an apparatus for treating articles of manufacture, a support foran article to be treated, means to move a body of air to the article, anebulizer arranged to introduce a cloud of nebulized material into saidbody of air moving toward said article, means under the control of theoperator for operating the ncbulizer, and means to prevent applicationto said article of material ncbulized under pressure below normal forsaid material.

11. In an apparatus for treating articles of manufacture, a support foran article to be treated, means to move a body of air to the article, anebulizer arranged to introduce a cloud of nebulized materials into saidbody of air moving toward said article, means under the control of theoperator for operating the nebulizer, and a member arranged to beinterposed between the nebulizer and said article to intercept thenebulized material .for a desired period of time.

12. In an apparatus for treating articles of manufacture, a support foran article to be treated, means to move a body of air to the article, ancbulizer arranged to introduce a cloud of nebulized material into saidbody of air moving toward said article. means for effecting operation ofthe nebulizer, means comprising a time controlled switch arranged todetermine the length of time of operation of the nebulizer. and a memberarranged to intercept the nebulized material on its way to said article.

13. In an apparatus for treating articles of manufacure, a support foran article to be treated, means to move a body of air to the article, a

nebulizer arranged to introduce a cloud of nebulized material into saidbody of air moving toward said article, means under the control of theoperator for operating the nebulizer, and a member arranged to beoperated in timed relation to the nebulizer to prevent nebulizedmaterial from reaching said article.

14. In an apparatus for treating articles of manufacture, a support foran article to be treated, a nebulizer arranged to introduce a cloud ofnebulized material into air moving toward said article, pneumatic meansunder the control of the operator for operating the nebulizer, and meanslocated beyond the nozzle of the nebulizer and arranged to be operatedby said pneumatic means to control application of nebulized material tosaid article for a predetermined length, of time.

15. In an apparatus for treating articles of manufacture, a support foran article to be treated, a nebulizer arranged to introduce a cloud ofnebulized material into air moving toward said article, means foreffecting operation of the nebulizer, means comprising a time controlledswitch arranged to determine the length of operation of the nebulizer,and a member arranged to be operated in timed relation to the nebulizerto prevent the application of nebulized or partially nebulized materialto said article.

16. In an apparatus for treating articles of manufacture, a support foran article to be treated, a nebulizer arranged to introduce a cloud ofnebulized material into air moving toward said article, means foreifecting operation or the nebulizer, means comprising a time controlledswitch arranged to determine the length of operation of the nebulizer,and a shutterbetween the nebulizer and the article arranged to beoperated in timed relation to the nebulizer to prevent the applicationto said article of material nebulized under pressure below the normalfor said material.

17. In an apparatus for treating articles of manufacture, a chamber,means to circuate air in said chamber, a support for an article locatedin the path of movement of the air in said chamber,'a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,power means under the control of the operator for operating thenebulizer, and a member located beyond the nozzle of the nebulizer andarranged to be operated in timed relation to the nebulizer to controlthe introduction of the nebulized material into the chamber.

18. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamber, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,pneumatic means under the control of the operator for operating thenebulizer, and means arranged to be operated by said pneumatic means toprevent projection of the nebulized material into the chamber for sometime after the start of the nebulizing operation.

19. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamber, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,power means for effecting operation of the nebulizer, means comprising atime controlled switch arranged to determine the length of operation ofthe nebulizer, and a member arranged to be operated in timed relation tothe starting of the nebulizer to control the introduction of thenebulized material into the chamber.

20. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamber, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,power means for effecting operation of the nebulizer, means comprising atime controlled switch arranged to determine the length of operation ofthe nebulizer, and a shutter between the nebulizer and the chamberarranged to be operated in timed relation to the starting of thenebulizer to control the introduction of the nebulized material into thechamber.

21. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamber, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,pneumatic means for efi'ecting operation of the nebulizer, meanscomprising a time controlled switch arranged to determine the length ofoperation of the nebulizer, and a member arranged to be operated by saidpneumatic means in timed relation to the starting and stopping of thenebulizer for controlling the introduction of mavterial from thenebulizer into said chamber.

22. In an apparatus for treating articles of manufacture, a chamber,means to circulate 'air in said chamber, a support for an articlelocated in the path of movement of the air in said chamber, a nebulizerarranged to introduce a cloud of nebulized material into the air in saidchamber,

pneumatic means for effecting operation of the nebulizer, meanscomprising a time controlled switch arranged to determine the length ofoperation of the nebulizer, and a shutter arranged to be operated bysaid pneumatic means, said shutter beingnormally in position tointercept material from the nebulizer when the latter is 'not operatingand said pneumatic means being operative to withdraw said shutter whenthe nebulizer becomes operative at normal pressure.

23. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamber, a nebulizer arrangedto introduce a cloud of nebulized material intothe air in said chamber,pneumatic means for efiecting operation of in the path of movement ofthe air in said chamber, a nebulizer arranged to introduce a cloud ofnebulized material into the air in said chamber, pneumatic means foreflecting operation of the nebulizer, and a shutter arranged to beoperated in timed relation to the starting of the nebulizer forcontrolling the introduction of material from the nebulizer into saidchamber.

25. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamher, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,pneumatic means for effecting operation of the nebulizer, and a shutterarranged to be operated by said pneumatic means, said shutter beingnormally in position to intercept material from the nebulizer when thelatter is not operating and saidpneumatic means being arranged towithdraw said shutter when the nebulizer-becomes operative at normalpressure.

26. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for an article locatedin the path of movement of the air in said chamher, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,pneumatic means'ior efiecting operation of the nebu izer, a shutter infront of the nebulizer arranged to be operated by said pneumatic means,and means including said pneumatic meansarranged to withdraw saidshutter when the nebulizer reaches its normal operating pressure and toreturn said shutter when the pressure in the nebulizer falls belownormal.

27. In an apparatus for treating articles of manufacture, a chamber,means to circulate air in said chamber, a support for anarticle locatedin the path of movement of the air in said chamber, a nebulizer arrangedto introduce a cloud of nebulized material into the air in said chamber,pneumatic means for effecting operation of the nebulizer, a'shutter,spring means arranged to move said shutter to operative position infront of said nebulizer, and a piston operated by' the pneumatic meansand connected to the shutter to move the latter to inoperative positionaway from said nebulizer in timed relation to the start ing of thenebulizer by said pneumatic means. MAI'IHEW M. MERRITI.

